Mr Foley was kidnapped in 2012 while covering the Syrian uprising, and the Islamic State group posted a Web video on Tuesday showing his killing.

In the letter, Mr Foley says he was being held with 17 other hostages, and they passed the time by discussing films, sport and trivia and playing games made up of scraps found in their jail cell.

Mr Foley says the hostages were fed daily and given tea and coffee.

His parents say letters their son wrote were confiscated by his captors. So he asked another hostage who was about to be released to memorise his letter and recount it to his family after he was freed.

The family, from Rochester, New Hampshire, posted the letter on a Facebook page called "Find James Foley".